ELS - Week 5 Part 1 - Properties of Minerals

• Mineral


  define as a naturally-occurring, inorganic solid with definite chemical composition and on ordered internal structure.
• Characteristics of Minerals

  A) Naturally occurring

  B) Inorganic

  C) Homogeneous solid

  D) Definite chemical composition

  E) Orderly crystalline structure

  
• The presence and intensity of elements and impurities or even its atomic composition determine the color of the specific minerals
• Streak


  it is the color of a crushed mineral's powder
• Hardness


  it is defined by how well a substance will resist scratching by another substance
• A scale to measure hardness was devised by Austrian Minerologist Frederick Mohs' in 1822 and is the standard scale for measuring hardness
• The specific gravity of minerals refers to the measurement that determines their density
• Luster


  It describes how a mineral appears to reflect light, and how brilliant or dull the mineral is.
• Fracture


  is a characteristic mark left when a mineral chip or breaks (Irregular Surface)
• Cleavage


  describes how a crystal break when subjected to stress on a particular plane (Smooth Surface)
• Luminescence


  occurs in some mineral when they are exposed to low-powered sources of ultraviolet or infrared electromagnetic radiation (example is portable UV lamps), at atmospheric pressure and atmospheric temperature
• Three electrical properties apply to minerals 

  Conduction, Pyroelectricity, and Piezoelectricity.
• Conduction 


  in mineral terms is defined as the ability of a mineral to conduct electricity. Only a very small number of minerals are good conductors; they are the metallic elements and the mineral Graphite. 
• Pyroelectricity


  describes the ability of a mineral to develop electrical charges when exposed to temperature changes. Some minerals develop an electrical charge when heated, others when cooled.
• Piezoelectricity 


  describes the ability of a mineral to develop electrical charges when put under stress. Piezoelectric minerals will develop charges when rubbed or struck repeatedly.
• Radioactivity


  is an attribute of minerals that contain radioactive element
• Water Solubility and Taste 


  is not the first (or possibly even the last) property someone would associate with minerals. And yet, the taste is sometimes a very good character and a key to identification in some cases. The most commonly "tasted" mineral is halite or rock salt, but there are several other minerals that have a distinctive taste
• Efflorescence 


  loss of water from the chemical structure of a mineral
• Deliquesce


  absorption of water into the chemical structure of a mineral
• Transformation


  happens when under stress, heat light
• Decomposition 


  a small number of minerals do this in certain circumstances
• Tenacity 


  It tells how well a mineral resists breakage
• Brittle 


  mineral crushes to angular fragments
• Malleable 


  can be modified in shape without breaking; can be flattened into thin sheet
• Sectile


  can be cut with a knife into a thin shavings
• Flexible


  mineral bends but doesn’t regain its shape
• Elastic


  mineral bends and regain its original shape
• Acid Reaction


  the object reacts to hydrochloric acid. The bubbles of carbon dioxide gas are the result of the type of carbonate mineral, amount of carbonate, particle size present, and the temperature of the acid.
• Crystal Shape 


  minerals are sometimes found as well-formed crystals. The shape of these crystals can often be used to identify minerals.
• Locality


  the type of a mineral is where the original material came from for the formal definition of the mineral species.